Art of coking coal



UNITED. -sT-Ai1-l-:s

` ARTHUR n oBERTs, or EVANS-TON, ILLINOIS,

PAT

oHEm'IoaL COMPANY, orcHIc2ieo-, ILLINOIS, A CORPORATION-or MAINE.

, orcoKING con@ Application med December I; 1ers; seriai'm. 341,696.

tion.

Jby-produ'cts.

This invention has todo with certain iInprovements in the art of coking coal for the production oflcoke, and the recoveryl of The present invention concerns itself particularly with a process for the production of coke and by-products from certain classes of coals.

`The present invention has particular reference to improvements in this art whereby it is possible to produce satisfactory metallurgical coke from a large classjof -coals which have heretofore beenjclassed as noncoking. Byway of introduction, 'I may 1 state'that for many years it has been well ing the kind of coals previously-considered.

understood that metallurgical coke could i be produced by the 'coking processes as prac- '25 tised when applied to a comparatively limited class of coals. The percentage of workable coals available for the manufacture of metallurgical coke 'in the United States by previous processes has been and is small, compared to the total amount of coal'.

To get athorough understanding of the present invention a brief statement concernas av ilable for 'coking, and a comparison of cer ain characteristics thereof with those coals which have refused `to yield metallurgical coke when subjected to previous processes is essentiah In general coke. 'is i L formed by binding-the fixed carbonfand ash 4of and from the volatile hy'drocarboncontained 'in' the original coal.

undergo certain of a' cementing material which is made out :All coals when -sub'ected the retort and for the formation of Coke l physical and chemical pends upon the original composition land structure of the coals and the 'heatftreatr ment to which they are subjected.. The'.

general classification of'coals as to whether they are cokingfor non-coking has been based'upon results obtained 4when. subjected "1 to heat treatment according to previous processes. AFor purposes of convenience 1nA this process.

to. treatment-in changes; the vresultv of .these changesv de-f'j.

wwwofLettersftentk-f Patented-Sept. 14, S1920."

Y explanation, -I shall use this terminology. in Y this specilication;'but itwill be understood at the-begmning that the expression nonf coking 1s-- incomplete lexcept l ascoupled with a Astatement or explanation concerning the'process to whlch'the coal is subjected;

vand is, therefore, a misnomer, since coals which have refused to'yield metallurgical coke under previous vprocesses will yield i `metallurgical coke when treated Aby the Apresent process. Accepting the 'previous momenclature for simplification in'explanation, I vwill state that research and analysis t show those coals previously classed as cok vmgf coals fall into a very different category of structure and composition from those previously classed as fnon-coking.

In a general way this dierence in structure and composition bears fa definite relationship to-ge'ologlcal conditionsand treatment to' whichsaid coals were subjected during formation. As a rule, the .coals which, by

previous processes, lhave yielded I metallurgi- .cal coke have'been ofthe higher rank such.

as the semi-bituminous coals.' 'The larger percentage .of the bituminous coals have -failed to yield metallurgical coke vby prev-ious processes. 'Such coals will yield excellent metallurgical 4coke in commercial vquantities when subjected to treatment by To form cokev ofmetallurgical structure the particles ofL 'carbon'` and other solid re- "siduum must be bound together by a cementing material which mus t be formed at the right time and underv the properconditions.

the solid residual matter, anda binder to 'i join vtogether the particles thereof into a constituents of the` coal together by means i i -chanical strength and porosity. Theresidhomogeneous lcoke structure of proper meual matter is available from all types of rocesses; But

constituents' from and out of which Lthe 'evolved ordformed as Va producti'ofdistilla- -The two essential elements, therefore, are

10 bindingmaterial ishmade when subjected to v -l-,ithis process. 155' V" Thebinding material is not' one of the V `conetituent -compounds of? coal, but, is"

' able one.

ing action can be The volatile constituents contain resinous materials or resinoids and humus materials, or humoids. The cementing or binding agents are derived chiefly from the resinous materials. The process must be such as to convert the resinous materials into cements` or binding agents of necessary strength and quantity at the right time and in the proper manner or coke will not be formed.

If thev application of heat be without reference to intensity and time, the resinoids may be vaporized and passed off slowly without much alteration in composition; consequently, but little if any cement is formed; but if rapidly heated with the quantity of heat per unit of time under control they will be decomposed with consequent liberationof hydrogen' gas and concentration of the carbon, so that'the resinoids in their changed form will fuse or become plastic or viscous and capable of acting as a cementing agent. The distilled gas carries lthe rapidly forming cement into the coking mass impingingit against the individual disconnected particles of residuum, surrounding them with a mass ofplastic or semi-plastic or viscous material which is being rapidly and continuously formed. As this action proceeds into the mass of coal, further and secondary decomposition takes place with a resultant enriching and hardening effect, binding the previously disconnected residuum particles together into a firm metallurgical structure or coke.

The resinous hydro-carbons melt and become plastic at 300"-to500o C., so that they are then able to flow around the particles of residuum and lill the interstices between said particles to bind them together as and when said binding material becomes sufficient in quantity and strength. At a later time when the .temperature of 600O to 750O C. has been reached, said resinous materials may, if present in sufiicient quantities,fbe further decomposed with the formation of the cementing agents and the consequent binding action above explained. Therefore,A if' the cementing function is t`o take place for the formation of a metallurgical structure, there must be present, when the temperature of 600C to 750 C. is reached, a sufficient amount or proportion of resinous materials "distributed throughout the mass and Vremaining in such condition that the cementperformed by decomposition of these bodies.

In order to bring about the ultimate formation of metallurgical coke a certain proportion of binder or cementing agent must In the so-called coking present is so large that a suicient propor tion of binding material will be formed almost without regard to the process or manner of application of heat treatment, whereas in the so`called non-Coking coals, the proportion of resinoid-s is so small that special consideration must be given to a process producing the heat treatment necessary to increase the production and conserve the binding material from said resinoids.

During thecoking process, two factors or conditions diametrically opposed tothe formation of coke are constantly atfwork tending to defeat or prevent the formation of the coke structure. The first of these is the tendency of the resinoids to evaporate ing mass. This is a bodily removal of`material from which the binder must be formed and, therefore, directly lowers the percentage of the material which should be available and which is necessary for the formation of binder.

' The second facto'r is the tendency toward the internal destruction or alteration of the resinoids in rsuch a manner as to also lower the amount available for cthe ultimate production of binder.' This internal destruction is a chemical reaction between the constituents of the resinoids and other elements present in the coals chiefly oxygen in such form that thesame can'combine and re-act with the resinoids and hydrogen.

The percentage of available oxygen present in the raw material is more or less a characteristic of the geological age of the material. As a rule, the coals of younger geological age run relatively higher in oxyen kthan those of older geological age, and 1t a so well understood that the coals of the younger geological age cannot be coked by previously understood and practised processes.

The manner in which the percentageor `am`ount of total oxygen varies with the geological age of the coal will be appreciated from the following comparison of oxygen content of coals of-various ages:

A typical class of wood contai\ s 83.07 parts of oxygen per 100 parts of cafhon;

A typical class of peat conta-ins` 55.67

parts of oxygen per 100 parts of carbbn;

A typical class of lignite contains 42.42

parts of oxygen per 100` parts of carbon;

` Ax. typical class of sub-bituminous coal contains 21.23 parts of oxygen per 100 parts of carbon; A typical class of bituminous coal contains 18.32 parts of oxygen per 100 parts of carbon.;

A typical class of semi-bituminous coking coal contains 5.28 parts of oxygen per 100 parts of carbon; and

A typical class of anthracite contains 1.74 parts of oxygen per 100 parts of carbon.

that the percentagevof oxygen in the socalled coking coals 1s very much less than in the so-called non-coking coals.-

The natural tendency of the available oxygen in the coal is to combine with the hydrogen and' carbon of the resinous materials, breakin them down and resulting in what is, in e ect, a slow combustion thereby destroying the material from which the cementing agent is formed. As the temperature ofthe mass is raised in the retort, the aflinity of the oxygen for the other elements becomes greater and therefore at the time materials are ready to be converted into binding materials to perform their cementing function, the Vavailable oxygen is very active chemically. lTherefore, to be successful the process must be such as to quickly eliminate these oxygen compounds.

Such available oxygen as does not combine withthe resinous matters is eliminated with' the gaseous material. The problem, therev fore is to eliminate the oxygen with the gaseous material before it has sutlicient time to decompose the bituminous or resinous matter, so that the latter Will maintain the cementing qualities throughout the periody of carbonization. It should be nation with theihumus constituents (as is the factor since it can then readily surrounding it during 'thereis to destroy which becomes the case in the most marked degree in the hlmus types ofcoal), such as the younger and socalled non-cokirig coals,',the oxygen is .easily broken loose and becomes a serious combine with the hydrocarbons of the resinous materials the distillation period, and thus prevent their conversion into cementing materials. On the other hand, with the regular so-calledl coking coals when the oxygen is in combination with resinous constitutents which have large percentages of pitch forming, hydrocarbons from which the binding materials are derived by decomposition, we have a condition in which the deleterious eHect of the oxygen will not be so pronounced. This is because during the. heating process the volatile hydrocarbons are evolved in percentage large enough to oset the effect of the cementing agents. The

carbon in the coal mass in proportion 'to the percentage ofoxygen the less tendency that part of the residuum binder -or cementing agent by decomposition.' v

- Naturally the. oxygen has a clearly shows the fact;

yamountv of oxygen from the .the oxygen present.

ingV effect of the further conloose combi- 'process or the manner in which thel action strong affinity l 130 for hydrogen present inthe coal, and, therefore, the effectiveness of the oxygen in working its ldestruction of the resinous matter will be interferred with to a greater or less extent by the disposable hydrogen present. because the combination of the oxygen with such hydrogen will result in the formation of water or moisture which will be eliminated as such with thegases and vapors with a simultaneous removal of a corresponding coking mass. Therefore, inorder t'o examine conclusively into the effect .of the oxygen on the ability tocoke'the coal'we must find the relationship which the oxygen and hydrogen bear to .each other, since that relationship is the determining element in ascertainingv how much' damage or destruction It must be mentioned at this point that when the deleterious eect of oxygen is spoken of, and when beneficial or neutralizreference is-'had to those portions of' thetotal amount of these elements present which may during carbonization combine with each other for-the production o'f'water. We must subtract, therefore, the amount` of hydrogen and oxygen present in the form of water. The correctness of this reasoning will be further understood when it is borne in mind that the decomposition of the resinous -matters and their conversion into cementing material takes place at a temperature of 600o to750 C., so that water originally present is eliminated before the critical period is reached; Upon subtractin the amount of oxygen 'represented in the gHgO, we find present still a certain quantity'of oxygen.V This oxygen must beeliminated from the coking mass or it will destroy a portion of the resinous materials which will, therefore, cease to be available when and wherethe cementing function is to be4 performed. v

If the amount of resinousmaterials origi- ,y 'nally present be relatively large as is the case in `the previously classed coking coals, a substantial portion of'it may be deing coals-with so large an amountv of resinous material that a considerable portion may be destroyed lbyl the disposable oxygen and will be done by hydrogen `is' mentioned.,

still leave enough'to perform the cementing v function with-the production of coke even without paying' special attention to theA is performed. v

Examination of a nllmber of typical coals of both the so-called coking and noncoling varieties yreveal the following coin;

positlons I Hydro- Dis.

Coal. H dro. Ox gen. Dis. ox. gen: ox.

f y* y hydro' ratio. *a Acton Basin Ala.. 5. 15 8. 46 4. 94 6. 81 72. 5 Dolomite, Aia 4. 84 5. 94 4. 75 5.18 91. 6 Wheatcrol't, Ky 4. 53 8. 43 4.25 6. 17 65. 2 Brilliant, N. Mex... 4. 9] 8. 62 4. 81 7. 38 65.2 Charleroi, Pa 5. 09 7. 62 4. 94 6. 41 77. 1 Connellsville Pa... 4.64 7.47 4.52 6.61. 68.4 Greensburg, a 4. 82 5. 78 4. 71 4. 92 95. 7 Herminia, Pa. 4. 92 7. 76 4. 81 6. 86 70. 1 Millsboro, Pa. 4. 67 6. 43 4. 53 5. 30 85. 4 W `te, Pa.'- 4. 83 5. 80 4. 71 4. 83 97. 5 Fork Ridge, Tenn. 4. 95 8. 92 4. 74 7. 26 65. 3 Clarksburg, W. Va. 5.09 7.70 4.93 6.40 77.0 Kingmont, W. Va.. 5.26 7.61 5.11 6.41 79.7 Monarch, W. Va. 5. 04 8. 24 4. 88 9 6. 94 l 70. 3 Powellton, W. Va.. 5.04 6.39 4.93 5.50 89.6

`All of the foregolng coals have in the past been considered 'y coalsoand have been extensively used for the manufacture of metallurgical coke by previous proc-- esses.

The following coals, on the contrary, have in the past always been classified noncolring and have refusedvto produce metallurgical coke when submitted to previous coking processes Coal Hydro Oxygen Dis Dis ox {glrliilogg hydro' ratio.

Benton, nl 4. 90 11.94 4. 47 8. 48 52. 7 Bush, nl. 4. 85 12.11 4. 33 7. 87. 55. 0 ,35 Carterville 1 4.99 10.84 4.73 8.74 54.1 cennralia, ill. 4. 99 13. 82 4. 32 8. 4,9 50.9 4ceneen, Ill 4. 59 12.15 4.23 8. 44 5o. 1 Collinsville, nl. 4. 73 14.00 3. 98 7. 95 50. 0 Denlrvr'lle, nl 4. 91 10.95 4. 55 8. 97 I 51.9 Germantown Ill 5.06 13.57 4. 41 8. 42 ,l 52.4 Harrisburg, Ill. 4. 95 10. 55 4. 72 8. 65 54. 5 Herrin, nl.. 4. 94 12. 17 4. 48 8.07 54.9 Lincoln, nl.. 4. 75 11.15 4. 37 8.12 53. 8 40 Livr'ngst0n,1ll...... 5.11 14.62 4.32 8.27 52.2 Lrngszlen, nl 4. 92 14. 07 4. 30 9. 11 47. 2

- 0. Marron, nl 4. 92 12.99 4. 25 7. 69 5'. 4 Marysvillenl.. 4.52 10.23 4.29 8.40 51.1 New Baden, Ill. 4. 94 12.20 4. 46 8. 32 53. 6 orellnn nl.. 5.09 13.85 4.39 8.28 53.0 sprr'ngned, nl 5. 00 12.54 4. 43 8.08 54.8 45 Staunton, l 5.14 12.32 4. 59 8.74 53.5 Troy, nl 4. 94 15, 84 4. 30 10. 24 41. 9 W.rrenlrl0rt nl 4.88 11.25 4.57. 5 8.77 52.1 zelglennl.. 4.54 14.99 3.95 10.31 88.3 zer' ler, nl. 5.10 13.53 v4. 48 8.19 54.1

N 50 It Wlll be found upon comparison ofk the above examples that in every case the total oxygen in the coking coals is less than 10% and is greater than 10% in each of the non-coking coals. This fact shows the influence which the oxygen bears on the ability of previous processes to coke a given coa The above examples are given only as typical of the two classes 'of coking and non-coking coals so-ca'lled, but they serve clearly to show the relationship of the hydrogen-oxygen ratio to the coking ability of previously understood and practised methods 0f coking. The availablel olI disposable hydrogen present in the coal, after subtracting that portion represented by '20,-is available to partially. prevent the reaction of the oxygen on the resinous niaterials, because said hydrogen will combine with its equivalent weight ofoxygen, and these compounds are eliminated leavl-lg the resinous materials in .the mass in such condition that if treated by the proper process r they will be converted into binding material and perform their cementing function. The ratio of the vdisposable hydrogen to tlle disposable oxygen (after subtracting the Water present) therefore shows definitely the existence of a necessary function of the process required for the production of metallurgifal coke from that coal. This ratio is obtail ed y comparing the disposable hydrogen with the disposable oxygen,`as shown in the examples previously mentioned herein. If this ratio exceeds 58%, the amount of hydrogen present will be sufficient to combine with and eliminate such a percentage of the oxygen that the coal ishalmost certain to be converted into metallurgical coke if sllbt jected-to the previously practised processes. On the other hand if this percentage be less than approximately 58%, the amount of hydrogen present will not be enough to sulliciently reduce the damaging effect ofthe oxygen and the coal will not be converted to metallurgical coke by previously practised methods. Therefore, in general, coals in which the hydrogenfoxygen ratio is less than 58%, must be subjected process of this invention in order to convert them `into metallurgical coke. 1 It is to be observed that in comparing the disposable hydrogenwith the -disposable oxygen, for the determination of the ratios above mentioned, simply a comparison is disposable hydrogen as compared to the weight of disposable oxygen from the analysis of the dried coal.

For example, Connellsville, Pennsylvania, coal showed 4.52 percent of hydrogen and 6.61 percent of oxy en on a dry basis, this being the available ydrogen and theavailable oxygen capable of other. The ratio of 4.52 to 6.61 is 68.4%. As this is 10.4% greater than the Aabove ratio of 58%, this coal would be classed as a coking lcoal and would yield metallurical coke `by previously ractised processes. imilarly a Greensburg, ennsylvania, coal showed 4.71 pared to 4.92 percentage of oxygenV on a -dry basis, which percentages, when compared, give the ratio of 95.7%, hence this coal ranks as very high class coaking cool,

according to previous classifications.

to the improve-lre-acting with each percentage of hydrogen compercent available oxygen coal has been classified as non-colring.

. Again, a West Frankfort, Illinois, coal showed 4.57 percent .available hydrogen and 8.77 percent available oxygen on a dry basis, which iigures, when compared, show a ratio of 52.1% hence this coal has also been classed as non-Coking. In fact both of these coals have been considered non-coking. because previous processes have always failed to produce a metallurgical coke from them. l The general relationship which the total hydrogen bears to the total oxygen present ina coal, is influenced by the geological age following tables: Having reference to the particular samples of wood, peat, lignite, sub-bituminous coal, bituminous coal, semi--y bituminous coal and anthracite previously compared on the basis o f oxygen, we find- Said wood to contain 12.18 parts of hydrogen per 100 parts of carbon;

The peat to contain 9.85 parts of hydrogen per 100 parts of carbon;

The lignite to contain 8.37 parts of hydrogen per 100 parts of carbon;

The sub-bituminous coal to contain 6.12 parts of hydrogen per 100 .parts of carbon;

The bituminous coal to cotnain 5.91 parts of hydrogen per 100 parts of carbon;

The semi-bituminous coal to contain'4275 parts of hydrogen per 100 parts of carbon; and

The anthracite to contain 2.84 parts of hydrogen per 100 parts of carbon.

From the foregoing, we find the following comparison:l Wood 12.18of hydrogen to 83.07 of oxygen Peat 9.85 of hydrogen to 55.67 of'oxygen Lignite 48.37 of hydrogen -to 42.42 of oxygen 40 Sub-bituminous 6.12 of hydrogen to 21.23 of oxygen 5.91 of hydrogen to 18.32 of oxygen coking coa1'-4.75v of hydrogen to 5.28 of oxygen and-the Anthracite 2.84 of hydrogen to 1.74 of oxygen.

Comparing the hydrogen andpxygen in each case, we find the following: v

Bitumiiious Semi-bituminous i Wood 6.82 times as much oxygen as hydrogen Peat 5.65 times as much oxygen as hydrogen Lgnite 5.06 times as much oxygen as hydrogen '-Subbituminous coal 3.46 times as much oxygen as hydrogen Bituminous coal 3.09 times as much oxygen as hydrogen S e mi bituminous l i coking coal 1.11 times as much oxygen as hydrogen Anthracite .61 times as much oxygen as hydrogen We may now consider another'function of..

a process necessary for coking the so-called non-Coking coals, viz: the prevention of The resinous matters which, upon the application of a sulicient volume of. heat. per unit of time, may be converted into cementing material by decomposition will, if improperly heated, vaporize and ass olf in a gaseous state 'without being ecomposed of the coal. This is shown clearly by the (point of critical temperature.

sufficiently to form binding material. There- 1fore, even though these materials be not destroyed by oxidation, it may still happen that they will be removed from the retort in vaporous condition and be wasted or lost decompose the resinous matter forming ceinenting material.

The conversion of resinous materials yintof` l cementing or binding material, having reference to such portions as have not been destroyed by oxidation, consists in decomposing said resinous materials with liberation ofh drogen and deposition of carbon, or

the ormation of cementing hydro-'carbons ofa ,higher series and with a smaller-percentage of hydrogen. While there are many temperatures at which hydrogen can be separated `'from the hydrocarbons of coal in mass carbonization, still a large part of the hydrogen is driven 0H at a -period when the mass has reached a temperature between 600' and 750 C. indicating that this is the If the coal mass is not brought up to this temperature :at a rapid enough rate,'instead of eliminating the hydrogen from the carbon with the formation of binding materials and hence the formation of metallurgical coke, a large part of it will volatilize thereby vwasting the material from which thecement or binder would 'have been formed if properly decomposed. Therefore, -if a coke structure is to be produced from so-called non-coking coals, the temperature of each portion of the the lvarious particles are slowly` heated, a suiicient amount ofthe resinous material will be decomposed andlconverted into binding material,withconsequent formation of a coke structure. It will alsobe evident that in the case of said coals, vthe hydrogen-oxygen ratio is such that even though said coals be slowly heated a sufficient amount of resinous matter will remain Iwithin `their Lbody or'mass undestroyed by oxidation, and capable of conversion into binding material to enable the productiongof metallurgica l coke regardless of the process. O n, the other hand in the type previously known as nonpoking coals, the hydrogen-oxygen. ratio is so small that the heat must be very rapidly introduced so as to bring the coal up to decoking coals', the amount-or proportion of Aresinous materials is so large that even when composition temperature with consequent formation of a suicient amount of binder before an unduly llarge amount ofV resinous material is lost by evaporation. Therefore,

a'rapid rate of heat introduction is necessary in order to prevent destruction of the resinous materials by oxidation and to prevent wastage or elimination of said materials by evaporation before decomposition.

The formation of metallurgical coke structure from the lower rank coals will also be advanced or the character of the coke improved by the additional formation of binding material owing to the chemical action which I will now explain in detail.

It is the almost universal practice in retort coke ovens to transmit the heat from one or both faces of the chamber; the material adjacent to or in contact with said faces is the first to be subjected to distillation. As the volatile constituents are vaporized they travel away from the heating surfaces and penetrate through the relatively cooler portions of the mass undergoing treatment, and which have not yet had their temperature raised an equal amount'. Some `of these vapors are thus brought into contact with N masses of coalbelow their dew point; they are accordingly recondensed and on the kmass as tarry constituents. At a subsequent time in the process, when the heating action has still further penetrated into the mass, these same constituents are again partially revaporated and put into vaporous condition. This results in a concentration of the hydrocarbons.

This condensing of the tarry mass results in a concentration of the cementing material lalong a line that might be termed the outer border where the coal is being converted into coke, and, of course, said outer border is constantly traveling a greater distance away from the hotwall whence the heat is derived. In the case of the high volatile, high oxygen Vcoals, this concentration of the eementing material as it progresses away from the hot wall is very important. If the heat transmission is slow the rate of decomposition is slowed'down to a point where too.

much of these vconstituents will pass off in vaporous form. But if overtaken quickly by the heat of decomposition 'these materials will decompose forming the cement for binding theixed carbon and ash into a coke structure. This process goes on continuously from the beginning to the end of the coking cycle, there being an infinite vnumber of periods of the evaporation of the volatile matter, its condensation at a more advanced point, and its revaporation.

, Since the heat progresses from the heating source-the wall or walls-towardfthat part ofthe mass farthest therefrom, the center of the oven, it follows that the coking action throughout the mass is a progressive one, commencing atthe point or points nearest r1the source of heat and progressing away Ifrom the same until the entire mass has been penetrated by the heat, coke resulting if the deposited conditions be such as to bring about the proper treatment of the resinous material. The process of forming coke may be compared to a coking wave, one coming from each wallv progressing through the mass, traveling inwardly toward the center until its influence has been exercised throughout the mass; as the front of the wave of heat or coking action penetrates farther into the mass of coal, said mass is brought into such condition that it will be converted into coke if a regular coking coal, but if it be a socalled non-coking coal the conversion into cokewill not occur unlessthe crest of the wave reaches eachv point in its travel rapidly enough to catch the resinous materials and convert them into cementing material by decomposition before these resinous materials could be oxidized of the wave must be steep' enoughto bring about this conversion, or otherwise when the crest ofthe wave arrives the materials will have been removed from the mass.

It should here be noted that during the coking of the so-called non-coking coals according to this process, it has repeatedly been observed that the yield of hydrogen gas and the yield of fixed carbon in the coke structure are both greater than would have been expected from a prior analysis of the coal; the increased yield of hydrogen being explained by the decomposition of additional materials with consequent liberation of hydrogen; and the surplus amount of fixed carbon in the coke being explained by the deposition of carbon on the residual materials simultaneously with said decomposition. This aetion of evaporation, condensation, and revaporation, results in such a concentration of tarry material just in advance of the progressing wall or zone in which coking action is takingplace as to actuallytincrease the proportion of binding material to an amount greater than would naturally be expected considering the original composition of the coal. Therefore7 the rapid introduction of heat introduces a new step or operation, in the process of forming a coke structure, which is vital to a process tobe used to coke the coals previously classed as non-coking. This is a new result following directly from the introduction of the required volume of heat per unit of time, and is in the nature of an intermediate or supplemental step.

It has been explained that at temperatures of about 600O to 700" C., the resinous materials are decomposed with consequent liberation of hydrogen and creation of new, heavier hydro-carbons having a smaller percentage of hydrogen and `capable of acting as cementing materials. If the coking operations were to cease at 700 C., there would still remain considerable percentage of volatile matter in they residual product,

or vaporized. The front carry i perform the action lized. Consequently, it is the .practice to that the volatile constituents will be more nearly completely eliminated, this being insured ata tem erature in the neighborhood of 1100 C. I he vapors or' gases liber ated between 7 00-'1100 C. serve to improve the cell structure of the coke and also to harden cementingmaterial `and thus in# sure the formation of a hard, rm, coke structure of the physical quality to meet the needs of the blast' furnace and other metal' lur 'cal uses.

`he rate of heatpend on a 4specific degree of temperature being used in the retort wall, but upon the rate at which the heat units necessary to are driven into the mass of rawmaterial. Of' course, the tempera- Jture as an absolute amount isl one of the factors bearing on the rate of introduction of heat into the mass of coall in a'retort, but it is not the only factor, and, in fact, is not the most important'one. The rate of heat transmission from the heating gases in the combustion chamber within the` walls of the retort into the mass of coal is also influthe temperature up to such point' icientlyrapid transfer of heat units into application does not deenced by the resistance to the transfer of.

heat units; sothateven if very -high temperatures be present in theuesor gas pas.- sages as in the old processes, it may still be impossible to secure a sufficiently rapid introduction of the required volume of heat intothe mass cf-coal, to bring about the cre- -atipn of the desired product-,metallurgical co e.

It has been, and still is, the universal brick irl theconstruction of the heating walls ofthe retort, and such brick has a fusiontemperatur'e of approximately 17 50 C. so'that this is the absolute upperilimit of temperature, and, in fact, it is not practicable to use temperature above 1560o C. in theflues or gas paspractice to use silica l sages, since a 'sufficient'l margin of safety must be provided. Experience has shown increasing that even when using temperatures as high Aas -165()o C. in previous processes it has been impossible to securev a sufiiciently rapid introduction of heat units vinto the coking mass to` bring about the creation ofthe coking structure, in the so-called cnoncoking coals.

We must,therefore, look'to'the other fac tor in `order to solveethe problem of introducing the heat in a suciently rapid manner tol bring about the desired result. This other Afactor is the heat absorbing and transmitting capacity of the walls-for the v A transfer of heat units from the heating gases to the interior of the coal mass. By

the heat absorbing and transmitting powers of these parts to' a suiicient degree, it will. becomepossible to secure asufthe coal mass without the use of high temperatures. In this connection it should be remem'bered that it is notnecessaryto -attain high temperaturesin the coking mass itself, since the entire coking process can be completed inlany given particle of coal at a temperatureof 1000o C. or less. In

fact, it would be desirable l to be able to perform the entire process with tempera-Y tures in the combustion chamber of not to exceed, for example, 1000o C. which is being done by this process, since the wear and tear and spondinglyminimized.

' The rate yof heat transmission into the coking mass has, of course, reference to each and every particle which is to be made to yield-to' the lcoking function. The retort has a certain width, and it is customary to introduce the heat into the ing one or both 0f the walls. Wheri both of the walls are heated, the heat travels inwardly from yeach of themqtoward the center of the retort, and therefore the coking process, commencing at the walls, travels inwardly toward a dividing surface approximately at the middle of the retort, and which is more or less in the form of a plane. Since it ispractically the universal custom to heat both sides ofthe retort, the heat traveling toward the middle of the oven from each side, I will-hereafter make reference to such construction and describe operation, butin so doing I wish it distinctly understood that this is done simply as a matter of convenience in this specification, and not as a matter of limitation, since the same principles would apply if the retort were to be vhated on only one side or face, in which case the coal adjacent to the other side or face would be the last to reach l the conclusion of the process.

As the heat travels from the walls toward the center of the oven, it must pass through a constantly increasing thickness of niaterial, be the said material coal,` coke, or

icoal at some intermediate stage of transformation. All of these materials are realtively poor conductors of heat and, therefore, the rate of heat transfer to the middle of the oven is greatly impeded by the intervening material.

Assuming'the temperature in the heating Walls to be not greater than a predetermined amount, the `width of the ovenwould, therefore, be limited to such 'a distance as would permit of a suiicient'ly rapid raising of the temperature of the middle portion of the coking mass. This means that the tendency in the design and construction of the ovens should be toward the narrower retort in order to satisfactorily handle the noncoking coals. Reduction'in the width of lthe retort entails corresponding reduction retort by heatsuch ' in which the gases .throughout the 4entire coal in vprocess in cubical capacity and corresponding reduction in the amount of chargewhich can be coked at one operation. As a matter of economy in operation and earning capacity of the plant, the charge should be kept as large as possible. The volume of the retort can be only increased' by increasing its height and length, assuming that its width has been xed. The height and length of the retort are'limited, among other things, by the ability to uniformly heat the entire vsurface by the heating travel through the heating walls, the height is so limited. The length of the oven is largely limited by the ability to push the completed coke out vof the retort at the termination of the operation, since the 'total friction or resistance to pushing is increased by i n`- crease of length, and' since there is a ver large side thrust exerted on the walls `of the retort tending to displace them or separate them farther apart.

The use of a relatively narrow retort is also consistent ywith the previously explainedevaporation, condensation and reevaporation of the volatile constituents which constitute a portion of the cementing materials. This previously explained action of evaporation, condensation and re? evaporation tends to concentrate thecementing agencies in that portion `of the coal mass at the center of the chamber, and thereby correspondingly improve the conditions existing in that portion of the chamber, so that it becomes possible to carry the coking action through the entire mass Aof thev materiaLnOtWi-thstanding the fact that the rate of heat transfer in the middle portion of the chamber isv necessarily slower than in those .portions adjacent to l in rate'of heat transfer being compensated for by the condensation and revaporation of the cementing materials. y

This ability to carry the'coking operation width of the chamber is also aided by another factor, which is the fact that some chemical re-actions of the othermic while others are endothermic. The re-actlo'ns of formation of such bod1es as carbon dloxld, carbon inonox1d,methane,

water and ammonia are exothermic-in na giving off considerable quantities of heat, while the 'actions ofgenerating such bodies as benzene, ethylene.I carbon-bisulfid, cyanogen and tar vapors are endothermic innature, necessitating the absorption of large amounts of-heat in ture, resulting in order to bring them about. The heat from the exothermlc re-actions is less than that necessary for the endothermic re-actions,

andthe difference must, of necessity, be supplied by the heat coming from the Walls of the retort. Investigation has shown that at gases. In those cases downwardly y the Wallsthe difference 'should be available in the of carbonization are extemperatures between 600O to'750 3 C. prac` tically all types of coals display exother- 'micity. Sincey the critical temperature for the fixing of the cementing agency is in the neighborhood of 600o to 7 50O C., it follows that at the very time when therejsinous materials are being converted into cementing material exothermic re-actions a corresponding improvement of the conditions under which the conversion may take place. By rapidly. raising the temperature to this critical point, not only is it possible `to bring about the conversion of the cementingmaterial, but also advantage may be taken of the exothermicity to assist the reaction.

The heat for the coking process comes, in the first instance, from the heating gases ytraveling through vthe flues or passages.

occur, with charged, there will commence a rapid transfer of heat from the walls and oven structure into the coal, with a consequent demand upon said reserve or supply. This demand will result in a corresponding lowering ofthe temperature of the wallsand structure, and disregarding for the moment the extraction of fresh heat from the heating gases), the ability to raise the temperature of the raw materialfwill depend chiefly upon the amount of this reserve as compared to the amount of coal in the retort, If. the coal be of the socalled non-coking variety, its temperature., must be rapidly raised to the point at which .the binding materials are formed, and this supply of heat oven structure. The amount of this K,reserve of heat is partially measured by a comparison of the weight of the walls and lhot vstructure with the weight of the coal, taking account of the specific heat ofthe walls and structure. In the case of silica brick constructions, this lmeans that a large reserve.

.specific heat averages approximately .20( asl ,compared to water as 1.00. l tice, the heating gases are atall times trans- In actual prac-4 ferring live heat to the ywalls of the -structure so that the reserve is4 supplemented.

As long asthere remains a Zone of coal which is not fully coked, the temperature of the coking mass cannot rise'greatly above the point at which decomposition takes place, although it will be understood that necessarily the mass close to the walls is always .hotter than the core or central portion of the mass. As Soon as the coking process has been completed by practically complete elimination of the volatile constituents, the temperature of the entire mass will rise rapidly, thus showingv that the operation has been completed and that the coke should be pushed.

The curves in the accompanying figure are typical of the temperature changes taking place in a typicall retort oven lwhen using the present process for coking theisoi called non-coking coals. These curves are illustrative of action at various points in the retort, and are in no sense to be considered as limitations upon the'use Aor practicev of the present invention and process, or as being in any sense a narrowingof the sco e of the present invention which is defined 1n and coveredby the claims.

Bearing this in mind, curve 10 shows a typical variation of wall temperature with respect to time, and curves 11, 12, and 13,1

' taking place at anyl point within the mass is the elimination -of the original moisture..

1t isobserved -that vall of the curves rise rapidly to the knee designated at the point A where each curve becomes practically flat until the original moisture has been evaporated. Thereafter, the individual curves rise more or less rapidly.l The curve 11 rises most rapidly because it represents a point closest to the wall. point B representing approximately 700 C., where it rests for a considerable intervalot time, portion C; During this interval the resin ous mattersare being decomposed with consequent liberation of hydrogen and formation of binding or cementing materials. During this time, also, additional heat is. being transmitted to points farther from the Wall and'nearer the core. The curve 12 rises somewhat slower and at-a later time to a kneeat the" oint D'representing approximately 700 (Iwwhere it also rests for an interval ofrtime durin the period of decomposition and formation of binding material.

The Vcurve 13 representing the conditions at the'core rises latest to the point vE being somewhat lower in temperature than the knees B and D, since (on account of the evaporation of tarry matters from the zones nearertthe wall and their condensation near.l

It reaches a knee at the" as shown by the relatively flattenedV This, in turn,

the' core), the conditions at that point are more favorable for the production of binding or cementing agents. On account' of such concentration of tarry material and consequent improvement'of the coking conditions, it is unnecessary to raise the Vtemperature of the core as rapidly or to the same degree in order to secure a suicient amount of binding material for the formation of the metallurgical coke structure.

After the decomposition action, the tempoint F, commencing first in the material closest to the wall and progressing toward' the central zones.

This rise of temperature ateach zone continues to the point G represented by 1000-1100 C., and between the points F and G higher boiling hydro-carbons are being liberated and brokenup or delivered `from the'mass so as to complete the devolatilization of the coke structure. Therefore, the oven should be pushed substantially at the time represented by the point Gr. 'After this point is reached, the temperature rises rapidly without correspondingbeneficial result, and there is apt to be an overheating of the oven walls, since' 'ioy perature begins to rise substantially at the I there is no volatile matter present` to absorb the heat and hold down the temperature.

Substantially between the points B and F, there takes place the. decomposition of resinous materials'with conversion of bindingl lor cementing material. The endothermic actions redominate in this portion ofthe process. ub'sequently the exothermic actionsv occur.

i The important'- relationship which the heat reservoir inthe wall bears to the process of this invention for the production of metallurgical coke from the so-called non-coking coals, is well illustrated by the curve l0, and its relationship to the other curves Y of this ligure. It is observed from the introduction of the coal down to the point lrepresented by J, curve 10 is falling, indicating that the wall isgiving up heat previously stored in it, and is, therefore, enabling a. more rapid penetration of the heat into theI coking mass. The point J is opposite to that portion of the curves'11, 12"and 13 which represent decomposition of resinoids'l and the formation-of bindingmaterial. The

rapidity with which the curves 11, 12 and 13 are brought up to this decomposition temperaturca is largelydependent `upon the delivery of heat previously stored in the walls.

vdepends largely on the mass of the walls and arrangement of the heating structure as compared to the mass of coal in the charge.

.It is observed that the curve 10 rises after reaching the point J showing that y after practically the entire mass has been raised to the decomposition temperature, where it rests more or less .uniform for a period of `to give up its heat rapidly on pound of coal in the retort, there will be a ture maximum temperature preparatory to .the

next charge.

i If there be provided approximately 3.8 pounds of Wall and Wall structure (arranged sufficient reserve of heat available to coke the high volatile high oxygen non-coking l -coals by the practice of the present invention, provided the nature of the Wall strucbe such as to rapidly absorb heat from the `heating gases, and also provided thatthe A Weight of coal in the retort be not excessive as compared to the area of the Walls of the retort. Of course,

account should be takenof its specific heat and conductivity as silica and the Weight factor correspondingly modifiedin inverse ratio Which the average specific heat ofsuchother material-bears to that of silica Which averages .20.

In order to most perfectly transfer the heat from the gases into the Wall structure, the passages in said structure should be relacomplex and small enough to insure a of all portions of the gas The smallness of these passages is to so-me extent limitedby the abilityto pro-vide suiii'- cient lcross sectional area for the transfer of the necessary volume of gases Without unduly limiting or .impeding its flow. However, if the total c'ross sectional area of the passages .be made approximately equal to,

that of the intervening blocks or structure, a very satisfactory proportion will be realized for the process of the present invention.

The ability of the coal massto absorb the heat from the Walls and thus ,bring about the rapid rise of temperature and rapid de- 'composltion combined `With the concentra tion and evaporation of tarry'materials is largely dependent upon the mass of coking material per unit area of heating'surface in the retort. This amount or ratio should be kept as small yas possible in order to reduce as much as possible the demand for heat from each unit of area of heating surface.v

This reduction, however, Ameans a 'corresponding narrowing of the retort. If the Width ofthe retort be made froml 12 to 16 inches, it Wil'lbe found `possible to coke practically all ofthe bituminous non-coking coals by the process of thepresent invention. It may also be stated thatV if the amount of coal in the .retort be made'approximately 29-30 pounds per square foot of Heating demand) per if other material than sllica be used for the Walls and hot structure,

compared to that ofA ratio as small as possibleso as to enable the most rapid introduction of heat into the coal from the heating gases. f the structure be such that approximately l2 to 13 pounds of coal be present in the retort per square foot of surface in the heating gas passages,- practically all. of they bituminous coals can 'be coked by the process of the present invention. In like manner it is desirable 'that the area in theheating gas passages should beas large as possible compared to the area ofy heating surface in the retort. If the area exposed to the heating be approximately V2.25-2450 times as large as the area of heating surface in the retort,

gases in theA passages' it Will be possible to coke practically all of the bituminouscoals by the process of the present invention.

.l/Vhere, in the claims, I use the expression 1n ravs7 condition and substantially Without admixture of foreign substance, I mean that the coal is inserted or introduced into the retort in substantially its raw form or condition and Without the admixture of foreign substance 'for the purpose material from which to secure or form the binder or cementing agent. By the expres? sion raW condition or like expressions, lI do not mean that the coal is not broken up or even pulverized, since the raw coal may, of course, be broken up or pulverized without modifying its chemical condi/tion and properties, but rather'I mean that the coal is introducedv into the retort without previ.- ous coking treatment or the like. Naturally the exact degree of fineness or comminution of the coal will depend somewhat upon the Wishes of the operator, thing under the claims mentioned is that the coal should be used substantially Without of providing' but the essential any foreign substance, and Withoutv prior mixture-of a non-coking coal of low hydrogenv content .with foreign substances vof higher hydrogen content, such as various bi- In partuminous or asphaltic substances.

my 1nticular, and by Way of illustration,

vention and process may be successfully used,

to produce metallurgical coke from a mixture of lignite coal, having a low hydrogen content, with a coal o f higher hydrogen fconf" tent even though the proportions and chai'-l acter of the two be such that the hydrogen Y content of the resulting mixture falls considabove given is purely illustrative anfhis not lominous coals by the rapid introduction of` This results in the larger concentra- .to be in any sense considered as a limitation on the process of the present invention.

I wish also to emphasize the presence or existence of a new result in the process of coking the high Volatile high oxygen bituheat.

tion 'of the tarry resinous matters (from which the binder or cementingv material is derived) along a progressive zone within the retort. The temperature of this zone Iis raised so rapidly tothe necessary degree for decomposition of said tarry matters that the destruction by loxidation or elimination by evaporation does not prev'ent the formation of the metallurgical coke structure.

I am aware that ithas been proposed, as in the Engelmann patents (Nos. 136,592 and Reissuey No. 5,486) to coke lignit'ic coal by mixing therewith a suficient quantity of coking coal, or of bituminous or asphaltic substances, to produce a mixture approxi-l ofL bituminous coking mating the character coals; but by my novel process I am enabled to produce metallurgical coke not only from coals heretofore considered non-cokable, as described in the foregoing specification, but I am enabled to produce metallurgical coke from ook-ing mixtures, such as a mixture of lignitic coal with other coal of a higher hydrogen content, which do not approximate the character of bituminous coking coals, but which, on the contrary, like the Vsub-bituminous, bituminous and semi-bituminous coals referred to in the foregoing specification, fall considerably ybelow the 'content of hydrogen relatively to oxygen that is lfound in coals heretofore considered cokable.

I claim: l

1`. The process of treating coals to produce metallurgical coke in which 'said coals the amount of disposable hydrogen does not exceed approximately fifty-eight percent. yof the amount of disposable oxygen, which consists in charging such coal into a closed retort and introducing'heat into the coal mass through the medium of the retort and with the exclusion ofr air, the heat being introduced from the retort so rapidly that the temperature of each portion ofthe mass is raised to approximately seven'hundred degrees `centigrade before oxidationv of 4the resinous constituents -by the oxygen in the coal, whereby said resinous constituents are sists in charging the saine -the exclusion of air, l duced so rapidly that the temperature of -eacli portion of the mass Vcomposition of its resinous constituents the formation of cementing material and liberation of hydrogen in each portion of the mass before the destruction of the resinous constituents in such p'ortion by oxidation, and with consequent production of a metallurgical coke structure.

2. The process of treating coals to produce metallurgical coke in 'which s aid coals the decomposed with amount of disposable h .drogen does not ex-l i ceed approximately fi ty-eight percent. of the amount of disposable oxygen, which coninto a closed retort and introducing heat into the coal mass through the medium of the retort and with the heat being introeach portion of the mass is raised to the ltemperature of decompositionof its resinous constituents before oxidation 'of such resinvous constituents by the oxygen in the coal,

whereby said resinous constituents are decomposed with the formation of cementing material and liberation of hydrogen in each portion of the mass, before the destruction of the resinous constituentsA in such portion by oxidation and with consequent production of a metallurgical coke structure.

3. The process of treating coalsto produce metallurgical coke in which said coals the amount of disposable hydrogen does not expercent. of

ceed approximately fifty-eight which conthe amount of disposable oxygen,

sists in charging the same into a closed re heat into the coal mass I the medium of the retortand withthe heat being intro-A tort and introducing through the exclusion of air, duced so rapidly7 that the temperature of vis raised to the point of decomposition of its resinous constituents before .oxidation of said constituents bythe oxygen in the coal, whereby the particles ofcoal are cemented together into a metallurgical coke structure before destruction of said resinous constituents by oxidation.

4. The process of ftreating high Volatile, high oxygen, bituminous coals for the .production of metallurgical coke, which consists in charging the same in raw condition and substantially Without admixture of foreign substance into a closed retort and introduciio ing heat into the coal mass through the medium of the retort and with the exclusion of air, the heat being introduced, so 4rapidly tion of the mass, is raised to the ,p oint of gee.. fore oxidation of said constituents by the oxygen present in the coal, whereby said that the-temperature of each por-1 resinous constituents are decomposed withx'.

the formation of cementing agents and liberation of hydrogen in the mass before the destruction of the. resinous constituents in such portion by oxidation and with consewith the exclusion ofair, the heat being in? lclusion of air, the

quent production of a metallurgicalcoke structure. 5. The process for the treatment of high volatile, high oxygen, bituminous coals having a relatively small percentage of resinous constituents present consists in charging the mass 1n raw condition and substantially withoutA admixture of foreign substance'into a closed retort and introducing heat into the coal mass through the medium of the retort and .with the exheat beingintroduced so temperature of each poris raisedI to the point of decomposition of its resinous constituents ybefore excessive oxidation of said resinous constituents by the oxygen present in the coal, whereby sufficient amounts of said resinous constituents are decomposed in all portions of the mass of coal with consequent production of cementing agents to bind the particles of material into a metallurgical coke structure. v 6. The process of treating coals to produce metallurgical coke in which-said coals the amount ofI disposable hydrogen does not exceed approximately fifty-eight percent. of the amount of 'disposable oxygen, which consists in charging the lsame into a closed rapidly that the tion lof the mass retort and introducing heat into the coal mass through the medlum of the retort and troduced -so rapidly that the temperature of each portion of the mass is raised to the point of decomposition of its resinous constituents before excessive oxidation of said resinous constituents by the oxygen present supplied.` from 1n the coal, whereby lsufficient amounts of said resinous constituents'ae decomposed in all portions of the mass of coal with consequent production of cementing agents to bind the particles offmaterialv together into a metallurgical coke structure.

7. The process of treating bituminous coals in which said coals the amount of disposable hydrogen present does not exceed approximately fifty-eight percent. of the amount of disposable oxygen present for the production of metallurgical coke from such coals, which consists in charging the same `into arelatively narrow retort and delivering heat into the coal from the retort with the exclusion of air, the heat being the sides of, the retort and v,proceeding toward ,themiddle of the retort from opposite directions to thereby volati- 'lize the low boiling hydrocarbons commencing at the sides and advancing toward the 'center` those hydrocarbons which are first -volatilized being recondensedv on the interior cooler portions of the mass with concentration of said hydrocarbons in such por tions, and being subsequently evaporated as in their mass, which' the middle ythe temperature formation of cementing material from such hydrocarbons, whereby there is created a progressive wave of cementing action within the mass commencing at the walls and traveling so rapidly toward the center of the retort as to form cementing agents at each point by decomposition prior 4to excessive destruction of said hydrocarbons by v oxidation. l

8. The process of treating high volatile, high oxygen, bituminous ycoals for the production of metallurgical coke, which consists in charging the same in pulverized condition raw and substantially without admixture of foreign substance tively narrow retort and delivering heat into the coal from the retort With-the exclusion of air, the heat being supplied from the sides ,of the retort and proceedingtoward of the retort from opposite directions, to thereby volatilize the low boiling hydrocarbons commencing at the sidesl and advancing toward the center, those h drocarbons which are 4first volatilized being recondensed on the interior cooler portions of the mass with concentration of said hydrocarbons in such portions, and being subsequently evaporated as the into the mass, the heat penetrating into the mass so rapidly'as to raise the temperature of each portion of the mass to the point of decomposition of the resinous constituents inl such portion before their excessive destruction by oxidation, taking account of their amounts` present by previous recondensation, with consequent formation of cementing agents from such hydrocarbons, whereby there iscreated a progressive wave of cementing action within the mass commencing at the walls and traveling idly toward the center of 'the retort as to form cementing material at each point by decomposition prior to excessive destrucinto a rela-` heat penetratesl The process of treating coals to produce metallurgical coke,

does 'not exceed approximately fifty-eight per cent. of the amount of disposable natural oxygen, which consists in charging the same into a retort andintroducing heat into the coal mass through the medium of the retort, the heat being introduced so rapidly- -that Vthe temperature of the mass is raised to of decomposition of its resinous constituents before oxidation of the entire content of such resinous constituents, whereby a sufclent resldue of such resinous constituents 1s decomposed to form the necin which said coals the amount of disposable natural hydrogen sists in charging the same in raw condition and substantially without admixture of foreign substance into a retort and introducing heat into the coal mass through the medium of the retort,- the heat being introduced so rapidly that the temperature of the mass is raised to the temperature of decomposition of its resinous constituents before the oxidation of the entire content of such resinous constituents, whereby a sufficient residue of such resinous constituents is decomposed to form the necessary quantity of cementing agents to afford a binder for the consequent production of a metallurgical coke structure.

11. The processof treating coals to produce metallurgical coke in which said coals the amount of disposable hydrogen does not exceed approximately fifty-eightv percent. ofthe amount of disposable oxygen, which consists in charging the same into a retort and introducing heat into the coal mass through the medium of the retort, the heat being introduced so rapidly that the temperature ofthe mass -is raised to the temperature of decomposition of its resinous constituents beforev excessive evaporation thereof, whereby asufiicient residue of said resinous constituents is decomposed in contact with the humous bodies in each portion of the mass to bind said humous bodies together with the consequent production of a metallurgical coke. v

12. The process of treating high volatile, high oxygen, bituminous coals for the production of metallurgical coke, which consists in charging the same in raw condition and substantially without admixture of foreign substance into a retort and introducing heat into thel coal mass through the. medium of the retort, the heat ubeing introduced so rapidly that the temperature of the mass is .raised to the temperature ofv decomposition of its resinous constituents before excessive evaporation thereof, whereby a y suiiclent residue of said resinous constltuents is'decomposed in contact with the humous bodies in each portion of the lmass to bind said humous bodies together with the consequent roduction of a metallurgical coke.

13. The process of treating high volatile, high oxygen, bituminous coals for the production of a maximum yield offcokewhich consists in charging the coals into a retortin raw condition and substantially without admixture of foreign substance and intro-l ducing heat into the coal mass through the :medium of the retort so rapidly that the temperature of the mass is raised to the point of decomposition of the resinous `constituents prior to their excessive dissipation by.r evaporation, whereby a maximum portion of said resinous constituents is decomposed with consequent deposition of carbon and increased yield of coke. x

14:.- The process of treating high volatile, highv oxygen, bituminous` coals for the production of metallurgical coke, which consists in charging the same into a retort of sufficient mass as compared to the mass of coal charged into it and of suitable temperature to insure the introduction of heat into the coal from the retort with" suflicient rapidity to raise the temperature of the coal to the point of decomposition of its resinous constituents before oxidation of the entire content of such resinous constituents, whereby a suliicient residue of said resinous constituents is decomposed to form the necessary quantity of cementing material to afford la binder with the consequent production of a metallurgicalcoke structure.

. 15. The'process of treating high volatile, high oxygen, bituminous coals for the productionof metallurgical coke, which consists in charging the same into a retort of sufficient mass as compared to the mass of coal charged into it and of suitable temperature to insure the introduction of heat into the coal from the retort with sufficient rapidity to raise the temperature of the coal to the point of decomposition of its resinous constituents, before oxidation of the entire content of such resinous constituents, whereby a suiicient residue of said resinous constituents` is decomposed inthe presence of the humous constituents tov form the necessary quantity olf cementing agents to afford a binder with the consequent production of a metallurgical coke structure.

16. The process of treating high volatile,

high oxygen, bituminous coals" for the production of metallurgical coke, which consists in charging the same into a retort of- 'to the point of decomposition of its resinous constituents before excessive dissipation by evaporation of said resinous constituents, whereby al suiicient quantity of said resinous constituent-s is decomposed Lin the presence of humous constituents to afford a binder with the consequent production of a metallurgical coke structure.

17. The process of treating high volatile,

high oxygen, bituminous coals for the pro-A duction of metallurgical coke, which consists in charging the same in raw condition and substantially without admixture of foreign substance into a retort and introducing heat into the coal mass through the medium of the sides of the retort, the heat clent amount Ofcementing material at 'each f point to bind the entire mass together ginto a metallurgical `coke structure. c 18. The process of treating high oxygen, bituminous coals for the production of metallurgicall coke, which con-- sists in charging the same into a retort of suitable temperature and thereafter intro-i duing heat into the charge through the medium of the retort,I the massof `theretort including its heating Walls being approximately 3.8 times as great as the mass of the material charged'into the retort, taking account of the specific heat of the retort maf terials, whereby there is insured the`intrioduction of heat into the coal from the retort With sufficient rapidity to raise the temperature of the coal to the po'int of decomposition of its resinous constituents before excessive dissoipation by evaporation of said resinous constituents, whereby a. sufficient .quantity of said resinous constituents is decomposed in the presence of humous constituents to afford a binder with the conse-l quent production of a metallurgical coke structure. y

19,. The process of treating high volatile, high oxygen, bituminous coals for the production of metallurgical coke, Which consists in charging the same into a retort of suitable temperatureand thereafter introducing heatinto the chargefthrough the medium cluding its heating Walls Abeing approximately 3.8 times as great as the mass of the 'material charged into the retort, taking achigh volatile,

Walls With passages of the retort, the mass of the retort incount of the specific heat of the retort materials, and the mass of coal. in the retort being approximately 29-30 pounds per square foot of heating surface of the retort.

20. The process of treating high volatile, high oxygen, bituminous coals for the production of metallurgical coke, which consists in charging the same into a .retort of suitable temperature and thereafter introducing heat into the charge through the medium of the retort, the' mass Jof coal in the retort being approximately 29-30 pounds per square foot of heating surface of the retort.

2 1. The process of treating high volatile, high oxygen, bituminous coals for the production of metallurgical coke, Which consists in charging the same into a' retort of suitable temperature and thereafter introducing heatinto the charge through the medium of the retort, the retort being provided in its side Walls With passages for heating gases, the mass of coal in the retort being approximately 12-13 pounds per square foot -sists in charging the same into a retort of suitable temperaturel and -thereafter introducing heat into the charge throughthe medium of the retort, the mass of coal in the retort bein approximately 29-30 pounds per square oot of heating surface of the retort, the retort being provided inits'side for heating gases, and the mass of coal in the retort being approximately 12-'13 pounds per square foot of heated surfaces of said passages. p p

r ARTHUR ROBERTS.

Witness: 1 THos. A. BANNING, Jr. 

